/*
 * TermInfo#tigetflag(capname) => int
 *
 * TermInfo#tigetflag returns a boolean capability specified by capname.
 */
static VALUE
rt_tigetflag(VALUE self, VALUE v_capname)
{
  int ret;
  setup(self);
  ret = tigetflag(StringValueCStr(v_capname));
  if (ret == -1) { rb_raise(eTermInfoError, "not a boolean capability"); }
  return RTEST(ret) ? Qtrue : Qfalse;
}